Any product that owns close to 90% of a market that is as gigantic as the global PC market would be considered a huge success. In the case of Microsoft, that is, of course, different. Windows has suffered from a continued market share decline since the 2003/2004 time frame and November 2008 was the first month in a very long time that Microsoft has dropped below 90%, 89.62% to be exact, according to Net Applications.

Net Applications has been providing operating system market share data since October 2004 and estimated Windowsí market share at about 96.4% at that time. In November 2005, Windows was down to 95.5%, in November 2006 to 94.2% and in November 2007 to 92.4%. Over the past twelve months, Windows lost 2.8 points of market share, more than in any other year in the operating systemís 23-year history (Windows 1.0 was released in November 1985.)